Presently, it is being discussed and proposed to introduce a very small base station targeted for certain or specified users for implementing FMC (Fixed and Mobile Convergence) services (see “Requirements for LTE Home eNodeBs”, RP-070209, 3GPP TSG RAN #35, Lemesos, Cyprus, 6-9 Mar. 2007). In LTE (Long Term Evolution), whose specification development is being currently ongoing, as a successor to the third generation radio access scheme, such very small base stations targeted for certain or specified users are collectively referred to as Home eNBs (or Home e-NodeBs). The Home eNB is a so-called plug-and-play type of apparatus that a user can buy and install at a desired location without the necessity, of operator's manual installation, maintenance and management.
Since the Home eNB serves as a private base station for certain or specified users, the Home eNB differs from general-purpose base stations constituting an existing public communication network, and it is not reasonable that all subscribers be permitted to access the Home eNB. Conventionally, in order to gain permission to access the general-purpose base stations constituting a mobile communication network, a user has only to subscribe to any communication operator and have user information registered with storage devices provided by the communication operator such as a HLR (Home Location Register) and a HSS (Home Subscriber Server). When the user subscribes to the communication operator, the user information is registered by the communication operator with the HLR. Before initiation of communications with a mobile station (user), the general-purpose base station targeted for the public determines whether the user is an authorized one through authentication of the mobile station based on the user information in the HLR.
However, it has not been conceived that access permission be registered for each base station. Acquiring access authority by subscribing to a communication operator conventionally means that it is permitted to access all base stations or a set of base stations (except base stations during maintenance) operated by the communication operator.